Extremely slow queries on Lakeformation governed tables via Athena

Hello, we are experiencing extremely slow queries against lake formation governed tables when using the Athena console and/or jdbc clients. For example, a simple count(*) of a three-row table takes something like two-three minutes and the execution details and data scanned indicate that this time is NOT being spent actually processing data. There is no cross-account data movement happening, and we are using parquet as our data storage format. The tables are being created by awswrangler. This is compared with low-single digit seconds for the same query against an external table. Any ideas what is going on?